Compilare: main.cpp: In function 'int dfs(int)': main.cpp:20:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 20 | for(int i=0;i<tree[node].size();i++) | ~^~~~~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:52:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 52 | for(int i=0;i<a.size();i++) | ~^~~~~~~~~